Impulse transmitter



Dec. 13, 1938. A. HQMILLEVR' 2,140,138

IMPULSE TRANSMITTER Filed Feb. 18, 1957 s Sheets-Sheet 1 sTAT KEY

Iunn-IEHEHHHEHHHE IIIIIII /Nl EOR ,4. H M/LL ER ATTORNEY Dec. 13, 1938.

A. H. MILLER IMPULSE TRANSMITTER Filed Feb. 18, 1957 3 Sheets-Sheet 2 o v n I x C IV? 54 f 76 RH M m MM a Mfl A ATTORNEY Dec. 13, 1938. A. H. MILLER IMPULSE TRANSMITTER 7 5 Sheets-Sheet 3 Filed Feb. 18, 1957 lHILI TE A TTORNEV Patented Dec. 13, 1938 UNITED STATES PATENT 'QFFICE Telephone Laboratories,

Incorporated, New

York, N. Y., a corporation of New York Application February 18, 1937, Serial No. 126,410

3 Claims.

This invention relates to signal transmitting devices for electrical communication systems and more particularly to code signal transmitting devices.

'The object of this invention is to provide a signal impulse sender which is simple in construction and of low cost to manufacture and which will give reliable and satisfactory service over a'comparatively long periodof time.

Afeature of the invention resides in the combination of a plurality of manually operated rotary switches with a motor driven commutator type switch and a relay adapted to control signal line contacts, the manually operated switches providing means for setting the device to transmit a required code signal and the commutator type switch serving to control the relay in accordance with the code signal setting.

In the drawings:

Fig. 1 is a front view in perspective of the impulsesending device;

Fig. 2 is a rear view in perspective of the device when a cover is removed;

Fig. 3 is a top plan view of the device shown in Fig. 2 and drawn on a slightly smaller scale than'Fig. 2;

Fig. 4 is a view in perspective of parts of one of the rotary switch elements used in the device, the parts being shown in their relative positions before being assembled. The parts in Fig. 4 are drawn on .an enlarged scale relative to Fig. 2;

Fig. 5 is a view in perspective of parts of another of the rotary switch elements used in the device, the parts being shown in their relative positions before being assembled. The parts in Fig. 5 are drawn to the same scale as Fig. 4; and

Fig. 6 is a schematic diagram of the impulse sending device and of a portion of a signal system in which the device may be used, the impulse sending device of the invention when used in combination with certain elements in the signal system serving to send code signal impulses over the line wires of the system.

The code signal transmitting device may be used in a selective signal system in which selectors at substations are remotely controlled by means of signal impulses-sent over the line wires of the system.

This invention while not necessarily limited to such use has been found particularly welladapted for use in a selective signal system used in train dispatching wherein a pluralityof selectors of the type described'in Patent 1,343,256 issued June 15, 1920, are located .at substations and are remotely controlled from a train dispatchers station. The

selectors are operated upon each impulse of opposite polarity to the one preceding it to step, a movable contact member one step toward a contactmaking position. When impulses corresponding in number and sequence to the setting of a par- 5 ticular selector have been received, that selector will operate to close a circuit to a signal device to cause the sounding or display of a suitable signal at that particular substation.

The code signal transmitting device may be used L 10 .in place of a. plurality of selector keys of the type shown and described in Patent 1,306,054 issued June 10, 1919, and also in place of the impulse sender shown and described in Patent 1,976,548 issued October 9, 1934.

With reference to the drawings and in which like parts in the figures bear like numerals, I3 is a box-like container comprising a cover 14 and a control panel [5. The cover 14 is in the form of a rectangular box with one open face and -zo serves tocover apparatus mounted on the control panel 15 and projecting rearwardly from the control panel 15. The control panel 15, as shown in Fig. 2, supports manually operated rotary type switches 16, I1 and 18 and a motor driven commutator type switch 19. The manually operated switches 16 and I! are used in setting the device to transmit a predetermined code signal. Theswitch i8 is used in setting the device to send impulses additional to the settings made by operacontrol handles for the switches 16, T! and 18 are located outside of the container 13, as shown in Fig. l, and the remaining portions of the switches extend rearwardly from the rear face of the control panel 15, as shown in Fig. 2, the control panel 15-being apertured to accommodate the shafts of the switches I6, 11 and 18. The control handles 80, 81 andBZ, shown in Fig. 1, apply to the respective switches 16, TI and 18, shown in Fig. 2.

The commutator type switch 19, as shown in Figs. 2 and 3, comprises a ring 83 of insulatingly spaced segmental fixed contacts 84, the contacts 84 being insulatingly supported on a ring 85 of insulating material. The ring 85 has a tubular neck portion 86 attached to a yoke 81. The yoke 8'! has outwardly turned apertured flanges 88 on its free end portion and is secured to the rear surface of the control panel by suitable fastening means 89. The yoke 8! is apertured at its closed end to permit extension therethrough of an arm 90. The arm 90 is L-shaped and is secured at one end to a motor 9| and carries on its free end a brush contact 92, the brush contact 92 engaging successively the segmental contacts 84. The brush contact 92 is so formed that some portion of it is always in engagementwith a segmental contact 84.

I have found that a spring driven motor of the type employed in the impulse transmitter shown in Patent 1,306,054 issued June 10, 1919 and which is commonly known as a selector key, serves quite Well as a motor for driving the brush contact 92 over the segmental contacts 83 and reference to this patent may be had for a full understanding of the structure of the mo tor. The motor 9|, therefore, is shown as being a spring driven motor in which a spring 93 is manually wound by means of a handle 94. The handle 94 is located outwardly of the front face of the control panel 15 and is mounted on a shaft 95, the shaft 95 projecting through an aperture in the control panel 15. The driving mechanism of the motor 95 is located rearwardly of the rear face of the control panel I5 in the space defined by the yoke 8'! and is supported by suitable means on the rear face of the control panel I5. The motor 9i includes a governor 96 which serves to control the speed of operation of the brush contact 92 over the segmental contacts 84. When the motor is to be operated, the handle 94 is manually turned to wind up the spring 93. Upon release of the handle 04 the spring 93 through a gear train 97 causes rotation of a shaft 98. A Wheel 99 is secured to the shaft 98. The arm 90 carrying the brush contact 92 is secured to the wheel 99. The spring motor 9|, therefore, rotates arm 90 and causes the brush contact 92 to successively engage the segmental contacts 84. Each segmental contact 84 has a bifurcated heel portion I00 which serves as a point of connection for a conductor wire. The conductor wires are not shown in Figs. 2 and 3, but are shown only in Fig. 6 in order to simplify the drawings. The conductor wires, as will be subsequently pointed out, however, serve as electrical connections between the segmental contacts 84 and predetermined contacts in the rotary switches 10, l! and l8. 7

The rotary switches 19 and I! are alike in construction and each switch has double and single switch elements. In order to simplify the specification, only one of these switches will be described in detail. Switch 11, for instance, comprises two sets of fiat rings of insulating material. The first set, generally designated by the number 19f, contains the double switch elements and comprises three pairs of rings of insulating material. The second set, identified by the number I92, contains the single switch elements and comprises three separate rings of insulating material. The rings of insulating material and parts cooperating therewith to form the switch are shown in detail in Figs. 4 and 5. Fig. 5 shows the construction of parts of a double switch element. Fig. 4 shows parts of one of the single switch elements. The ring I03 of insulating material, as shown in Fig. 5, serves as a support for aset of spaced fixed contacts I04. The spaced fixed 'contacts I04 are secured by means of discs 5 and us.

rivets I05, or by other suitable fastening means to one face of the ring I03 and project inwardly of the ring I09. The contacts I04 are in the form of spring fingers and have an embossed inner end I00 disposed within the open space defined by the ring I03. Apertured ear portions I01 are provided on the ring I03 to permit mounting of the ring I 03 on suitable supporting rods I08 in spaced relation with other rings of the set, as shown in Fig. 2. A ring I09 of like structure to the ring i03, and as shown in Fig. 5, serves as the other ring of the pair. Spaced fixed contacts II 0 are supported on the ring I09. The contacts IIO are of like structure to the contacts I04 on the ring I03. Apertured. ear portions III are provided on the ring I09 to receive the supporting rods I08. The rings I 03 and I09 arranged in pairs are mounted on the supporting rods I08I08 along with rings of the single switch element above mentioned and which will be subsequently described. The supporting rods I08 are secured at one end to a ring H2 and the ring I I2 serves in cooperation with a roller supporting arm I I3 as a detent device for the switch. An operating shaft Ii! of the switch extends through the control panel 15 and through clamping means, not shown, the clamping means serving to hold the switch against the control panel I5. Tubular spacers II4 supported on the rods I08 and disposed between the rings of insulating material, serve to hold the rings in spaced relation. Two discs H5 and H0 of insulating material are mounted in spaced relation on the shaft Ill. The disc II 5 fits into the space defined by the ring I03 and is rotatable therein. The disc I I6 fits into the space defined by the ring I09 and is rotatable therein. In each disc there is an elongated aperture H8 in the central portion to receive the shaft I I1. A series of elongated apertures I I9 is provided in each disc I I5 and I I6 and near the periphery of each disc. The apertures II 9 are spaced apart equal to one-half of the spacing of the embossed ends of adjacent contacts of the fixed contacts I04 or II 0 with the exception that at one point there is a double space, the contacts referred to being supported by the respective rings I03 and I09. That is to say, the apertures H9 in the disc II5 are so spaced that alternate apertures are in alignment with the embossed ends I 06 of the contacts I04 supported by the ring I03, and alternate apertures H9 in the disc H0 are so spaced as to be in alignment with the embossed ends of the contacts I I0 supported by the ring I09. The number of apertures H0 in each disc is equal to double the number of contacts supported by each ring less one. For instance, there are six contacts I04 supported by the ring I03 and there are eleven apertures I I9 in the disc I I5. There are six contacts H9 supported by the ring I09 and there are eleven apertures H9 in the disc IIB. When the rings I 03 and I09 are mounted on the rods I08, as shown in Fig. 2, and the discs IE5 and H6 are mounted on the shaft Hi, the embossed ends I06 of the contacts I04 and of the contacts H0 and the alternate apertures II9 in the discs H5 and H0 are in alignment.

A set of bridging contacts I20 is carried by the The bridging contacts I20 are comparatively short flat pieces of conducting material reduced in width at each end to fit into the elongated apertures H9 in the discs H5 and I I6 and to extend through the apertures H9 and slightly beyond the outer faces of the discs so as to make contact with the embossed ends I06 of the contacts supported by the rings I03 and :I09. In Fig. 5 the bridging contacts I with the exception of onerare all shown fitted into the'aper- 'tures'I I3 in the disc H5. The free ends of the contacts supported in disc II5 will fit into corre sponding apertures in the disc H3 when the parts areput together. The remainingbridging contact is shown inrposition ready to be'fitted to aligned apertures I22 in the rings I03 and I09 serve to hold the parts together. Spacers I23 are provided on the rivets to further maintain "the rings I03 and I09 spaced apart the required distance. Ends of the bridging contacts "I20 engage corresponding embossed ends I06 of the contacts I204 supported'by the ring I03 and embossed ends of the contacts I'I0 supported by the ring I09. All but one pairof contacts in the rings I03 and H39 are bridged'by the bridging contacts I20 when the switch is in certain positions. In other positions all "the fixed contacts are bridged at the same time. For instance, if the parts shown 'in Fig. 5 are assembled, contacts I04 supported by ring I03 will be conductively connected by means of the bridging contacts I20 to corresponding contacts I I0 supported on the ring I09, that is, with the exception of the contacts in the uppermost position. Since normally there is no bridging contact I20 for this position, the uppermost contact I04 on ring I03 will not be electrically connected to the uppermost contact'IIO on "ring I09. When shaft H1 is turned by means of the manually operated handle'BLthe bridging condition is changed accordingly. The switch is provided with a detent I I3 and moves in steps, each step being the distance of one-half space between adjacent fixed contacts on a ring. Rotation :of'the handle SI,

'for instance, one step in-a clockwise direction to the first number from zero position on the front 'face of the control panel 15 will result in the bridging of all of'the fixed contactsv Rotation for one step more will result in unbridging of the first fixed contacts to the right of the uppermost contacts I04 and H0 supported by the respective rings I03 and I99.

As shown in Fig. 2, there are three of the single switch elements controlled by means of the shaft I I1 which is also common to the double switch elements above described. In Fig. 4 parts of one of the single switch elements are shown. Each single switch element comprises a ring of insulating material I24. Supported by means of the ring 124 are spaced fixed contacts 125 corresponding in structure and arrangement to the fixed contacts I34 in "the double switch element above described. The fixedcontacts I25 project inwardly within the space defined .by the ring I24 and have embossed inner ends I125. A disc I21 of insulating material is provided to carry a movable contact of the switch element. An elongated aperture I28 is provided inthe central portion of the disc I21. The disc I121 fits into the space defined by the ring I24 of insulating material and has an elongated aperture 129 formed near its periphery, the aperture I29 being adapted to be brought into alignment with an embossed inner end I 23 of a contact I25. In the elongated 'aperture I 29 a contact I30 is collector ring I3 I set. The contact I30 is inthe iorm of a rivet or staple and has portions upset or flanged over on opposite faces of the disc "I21. One end of the contact I30 selectively engages the embossed ends 126 of the fixedcontacts I25. The other end of the contact I30 frictionallyengages a collector ring contact I3I. The collector ring contact I'3I is provided with a terminal I32 which is secured by means-of a rivet I33 to the ring I24 of insulating material, the rivet I33 being extended through an aperture I34 in the terminal I32 and through an aperture I35 in the ring I24 and then spun over or upset against the surface of the ring I24 to hold the terminal I32 in position. Spaced lugs I36 are provided on the A ring I31 of insulating material is provided to bear against the collector ring 'I3I to keep the collector ring I3I pressed against one end of thecontact I30 and to maintain the disc I21 in the space defined by the ring I24. The ring I31 is apertured at a plurality of points I38 in alignment with the spaced lugs I30-of thecollector ring -I3I. The free ends of the lugs I36 are turned over against the outer face of the ring I31 to hold the collector ring I3I and the ring I31 of insulating material together. Clamps I39 are provided to clamp the ring E31 and the collector ring I3I in place against the disc I21. The clamp I39 has a bifurcated free end'portion I40 which fits over a 1 portion of the ring I31. Apertured leg portions I4I on the clamp I39 are offset from the plane of the clamp and bear against the ring I24. The

leg portions I iI are secured to the ring I 24 by, means of rivets I42 which extend through apertion for securing the uppermost clamp. It is to be understood, however, that the clamp I39 shown on the extreme right of the figure is secured in like manner to the ring'I2'4. The clamps I 39, therefore, serve to hold the ring I31, the collector ring I3I and the disc I21 in a required position relative to the ring I24.

In Fig. '2 three of the rings I2 4 assembled with the parts just described are provided as the single switch elements in the structure of the switches 10 and 11. Fig. 4. shows a front View in perspective of the parts and Fig. 2 shows the assembled parts in perspective viewed from the rear of the assembly. Shaft II1, as shown in Fig. 2, extends through the elongated apertures I28 in the discs I21. The rings I24, as shown in Fig. 2, are mounted on the rods 103, the rods I08 passing through aperture ear portions I44 of the rings I24. The rings I24 are held in spaced on-therods I08. When the shaft H1 is turned, for instance, by manualoperation of the handle BI, the discs I21 are rotated within .the rings I24. When the contacts I30 are in engagement with corresponding fixed contacts and the handle is turned one step, contacts I30 will be moved out of engagement with the embossed ends I26 of the contacts I25 with which they were left in engagement at the last setting of the switch and to a position where they will not engage a fixed contact. Another one-step movement will bring the contacts I30 into engagement with the next contact I25. As'the knob 8| is manuallyrotated the contacts I25 are successively engaged by the associated contacts I30 upon each second "step movement of the switch.

The switch 18, as shown in Fig. 2, comprises two rings I45 and I46 of insulating material. The rings correspond in structure to the rings I03 and I09 shown in Fig. 5. Each ring I45 and I46, however, supports only three contacts I41 which correspond in structure to the, contacts I04 and III]. In the space defined by each ring I45 and I46 there is a disc I48 centrally apertured to receive the shaft I49. Bridging contacts, not

shown, but corresponding in structure to the bridging contacts I20 of the double switch element arrangement shown in Fig. 5, areprovided to normally bridge the contacts I41 supported by the rings I45 and I46. The rings I45 and I46 are supported by means of the rods I50. The rods I50 are attached to a ring I5I and the ring I5I serves in cooperation with the roller arm I52 as a detent to limit each movement of the switch to a definite step. The switch assembly is held in place on the control panel 15 by suitable clamping means, not shown. Spacers I I4 supported on the rods I50 serve to maintain the rings I45, I46 and. I 5I in required spaced rela tion. Since the switch 18 is constructed like one of the double element arrangements in the portion IOI of the switch 11 and the switch 11 has been described in detail, further description of the switch 19 is considered unnecessary, the only difference being in the number and spacing of the fixed and movable contacts and that the switch 18contains only a double element arrangement.

To explain the function and operation of the switches 16, 11 and 18 and of the commutator type switch 19, reference will now be had to Fig. 6 in the drawings. In Fig. 6 the switches above mentioned are shown in connection with a portion of the system adapted to send code signal impulses over line wires to operate selectors at remote points. The apparatus shown in Fig. 6 might be located at a train dispatchers station and operate to send code signal impulses. to substations to selectively operate selectors at the substations, the selectors operating to control signal devices. The selectors are not shown-since they do not form part of the present invention and they may be of a well-known type such, for instance, as shown in Patent 1,343,256 as previously mentioned. Switches 16, 11, 18 and 19 are identified in Fig. 6 by suitable legends. Switches 16 and 11, as above mentioned, are alike in structure and each comprises single and double switch elements shown respectively in Figs. 4 and 5. There are three single switch elements and three double switch elements in each switch 16 and 11. The single and double switch elements in switch 16, as shown in Fig. 2, are supported in spaced relation on the rods I53 which correspond to the rods I08 in switch 11. The single and double switch elements in switch 16 are controlled through operation of a common shaft I54 which corresponds to the shaft H1 in switch 11. The shaft I54 for switch 16 extends through the control panel 15 into operative engagement with the control handle 80. Contacts in the single and double switch elements, as shown in Fig. 6, are wired to segmental contacts of the switch 19. To simplify the drawings, the structures of the single and double switch elements shown in Figs. 4 and 5 are not shown in Fig. 6. The single and double switch elements, however, are identified by the letters S and D, respectively, in Fig. 6. Switch 18 does not contain any single switch element, but only a double switch element of the type shown in Fig. 5, but having only three pairs of fixed con" over a line system I56 in which selectors, not

shown, are included, the selectors being located at substations on the line and being connected across the line conductors I51 and I58. The line system is supplied with current from a suitable source of current supply such, for instance, as the main battery I59, when the double pole single throw switch I60 is closed and the line relay I6I is energized.

When the switches 16, 11 and 18 are in normal positions, such as shown in Fig. 6, and. the control handles 80, 8I and 82 are in the position shown in Fig. 1 and the switch I69 is closed, the code signal transmitting device of this invention will send, for instance, seventeen impulses when the commutator type switch 19 is operated. To operate the commutator type switch 19 the handle 94 is manually turned to wind up the spring motor 9|. Upon release of the handle 94 the brush contact 92 of the commutator type switch 19 is driven by means of the spring motor 9I over the segmental contacts 84 and successively engages each segmental contact. The spring motor 9| also causes rotation of a wheel I62 which moves simultaneously with and at the same speed as the brush contact 92. The wheel I62 closes a circuit for the line relay I 6|, the circuit for this relay remaining closed for one complete cyclic movement of the brush contact 92. The circuit for the line relay I6I may be traced as follows: Local battery I63, conductor I64, conductor I65, conductor I66, closed contacts I61 and I68, spring contact finger I69, conductor wheel I62, arm 90, conductor I19, winding of line relay I6I, conductor IN, to local battery I63. Line relay I6I will therefore be energized and complete through its front contacts and armatures the circuit from the main battery I59 to the line wires I 51 and I58. The line circuit may be traced as follows: Main battery I59, conductor I12, circuit breaker I13, upper pole of closed double pole single throw switch I60, conductor I14, back contact and upper armature of pole changer relay I55, conductor I15, upper front contact and upper armature of line relay I6 I, line wire I51, the windings of selectors, not shown, line wire I58, lower armature and front contact of line relay I6I, conductor I16, back contact and lower armature of pole changer relay I55, conductor I11, lower pole of closed switch I60, conductor I18 to main battery I59. Energization of the line relay I 6| results in the sending of a singleimpulse over the line wires. Each selector at the substations, not

shown, moves a contact one step toward the fixed contact on this impulse, but since none of the selectors is set to hold at one step and the wiper contact 92 of the commutator type switch 19 normally rests on a blank segmental contact 84 and has to travel over several blank segmental contacts 84 before the code signal begins, the selectors during this interval all return to normal position. The motor 9| continues to drive the brush contact 92 over the segmental contacts 84.

The commutator type switch 19 is shown in .Fig. 6 as having seventy-three segmental contacts 84. The switch, however, may have a few more or less of these segmental contacts and still be operative for this invention. The number of segmental contacts shown, however, has been found convenient since standard rings of this number of contacts are available and. the unconnected contacts provide a pause period sufficient to allow the selectors to restore after the initial impulse is sent when the switch I60 is closed and-the line relay I 5 is energized. The brush contact 92, therefore, normally rests on about the sixtieth or sixty-first segmental contact, the segmental contacts 84 being numbered consecutively from to I2.

When the brush contact 92 passes from segmental contact I2 to contact 0, it enters the portion of the ring of segmental contacts associated with the switches I6, I1 and I8. Assuming that the'switches I6, 11 and I8 are set for normal condition, that is, with the pointers of the control handles 3.0, BI and 82 pointing directly upward, as shown in Fig. 1, the first energization of the pole changer relay I55 takes place when the brush contact 92. engages segmental contact 6. The circuit for the energization of the pole changer rel'ay I55 through this point may be traced as follows: Local battery I53, conductor I64, conductor I65, conductor I66, closed contacts I6! and I68, spring. contact I59, wheel I62, arm 98, brush contact 92, segmental contact 6, conductor I80, bridging contact I20 in position 6 of lowermost double. element of switch 76, conductor I8 I, bridg ing contact I 20 in position 4 of central double element. of switch 15, conductor I82, bridging contact I20 in position 2 of uppermost double element of the switch, strap conductor I83 to position 0, conductor I 84, conductor I05, conductor I86, winding of pole changer relay I 55, conductor III to local battery I63. The pole changer relay I55 will. pull its upper and lower armatures against the associated front contacts and cause the. sending of an impulse out over the line system I56, the impulse being in the opposite direction to that sent when the line relay EI was first energized. The impulse sent over the line system I56 causes each of the selectors at the substation to step a movable contact one step forward toward a fixed contact. When the wiper contact moves off segmental contact 5 and on to segmental contact I, the pole changer relay I55-isdeenergized since there is no circuit. to the pole changer relay, segmental contact I being connected by conductors I6! and I88 only to contacts in the single elements of the switch not closed by a movable contact I30. The deenergization of the pole changer relay I55 causes release of its armatures and the armatures move. back against their associated back contacts. In this position an-impulse is sent over the line system I56 of reverse polarity to the impulse preceding. The selectors at the substations therefore step their movable contacts forward another step toward a fixed contact. On segment 8 the I pole changer relay I55 is energized over a circuit including segment 8, conductor I89, bridging contact I20 in position 8 of lowermost double element of switch I6, conductor I90, bridging contact I20 in position 6 of the central double element, conductor I9I, bridging contact I20 at position 4 of uppermost double element, strap conductor I83 to position 0, conductor I84 and conductor I85. On segment 9 the pole changer relay is deenergized since this segment is connected by conductors. I92 and I93 only to contacts of the single elements not engaged at this time by the movable contacts I30. On segment I0 the pole changer relay is energized over a circuit including segment I0, conductor I94, bridging contact I20 in. position. I0 of lowermost double element of switch. I6, conductor I95, bridging contact. I20

in position 8 of the central double element of switch 75, conductor E65, bridging contact I25 in position 6 of the uppermost double element of the switch, strap conductor I83, conductor E84, conductor I85. On segment II the pole changer relay I55 is deenergized since conductors i9? and I98 lead only to fixed contacts of the single ele ments not engaged by movable contacts E55. On segment I2 the pole changer relay is energized over conductor I59, bridging contact i20 in position I0 of central double element, conductor 200, bridging contact I 20 in position 8 of uppermost double element, conductor 20L bridging contact H20 in position II of uppermost double element of switch Ii, strap conductor 202, conductor 203 and conductor I85. On segment I3 the pole changer relay is deenergized since conductors 205, 205 and 205 are not connected to fixed contacts in engagement with movable contacts 535 of the single elements of the switches 56 and 5?. On segment I I the pole changer relay is energized over conductor 201, bridging contact i20 in position I! of central double element of switch ii, conductor 208, bridging contact I20 in position 8 of uppermost double element of switch ii, con ductor 209, bridging contact I20 in position it of uppermost double element of switch I6, strap conductor I33, conductor I0 and conductor i135. On segment I5 the pole changer relay is deenergized since conductors 2I0, 2II and 252 are connected to fixed contacts in single elements of the switches 1'5 and Ti not in engagement with movable contacts I30. On segment I8 the pole changer relay I55 is energized over conductor 2I3, bridging contact I20 in position II of lowermost double element of switch H, conductor 2M, bridging contact 525 in position 9 of central double element, conductor 2l5, bridging contact I 20 in position I of uppermost double element, strap conductor 202, conductor 203 and conductor I85. On segment A! the pole changer relay is deenergized since conductors 2I6, 2H and 2553 are connected to fixed contacts in the single elements of switch ll not in engagement with movable contacts I30. On segment I8 the pole changer relay I 55 is energized over conductor 2! 9, bridging contact I 20 in position 9 of lowermost double element of switch 11, conductor 220, bridging contact E20 in position I of central double element; conductor 22!, bridging contact I20 in position 5 in uppermost double element, strap conductor 202, conductor 203 and conductor I85. Onsegment I9 the. pole changer relay is cleenergized since conductors 222, 223 and 222 are connectedto fixed contacts in the single elements of the switch 11 not in engagement with movable contacts I30. On segment 20 the pole changer relay' is energized over conductor 225, bridging contact I 20 in position I of lowermost double element of switch TI, conductor 226, bridging contact I20 in position 5 of central double element, conductor 22.7, bridging contact I20 in position 3 of uppermost double element, conductor 209 and conductor I85. On segment 2! the pole changer relay is deenergized since conductors 228, 226 and 230 are connected to fixed contacts in the single elements of switch 1! not in engagement with the movable contacts I30. On segment 22 the pole changer relay I55 is energized over conductor 23I, bridging contact I20 in position 5 of lowermost double element of switch ii, conductor 232, bridging contact I20 in position 30f central double element, conductor 233 and conductor l35. On segment 23 the pole changer relay I55 is held energized over conductor 234, fixed contact in position 0 of uppermost single element or switch 11, movable contact I30 and conductor I85. On segment 24 the pole changer relay I55 is held energized over conductor 235, bridging contact I 20 in position 3 in lowermost double element, conductor I85. On segment 25 the pole changer relay is held energized over conductor 230, conductor 23I, fixed contact in position 0 of central single element of switch II, movable contact I30 in the same position, conductor 238 and conductor I85. On segment 20 the pole changer relay is held energized over conductor 238 and conductor I85. On segment 2! the pole changer relay I55 is held energized over conductor 239, fixed contact and the movable contact I30 in position 0 in the lowermost single element of switch II, conductor 240 and conductor I85. On segment 28 the pole changer relay is held energized since this segment is connected by the strap conductor 24I to conductor 238. On segment 29 the pole changer relay is held energized over conductor 242, bridging contact I20 in the B position of the double element in switch 18, strap conductor 243 between the B and C positions of the switch I8, bridging contact I20 at the C position, strap conductor 244 between the C and D positions, bridging contact I20 at the D position and conductor I86. On segment 30 the pole changer re lay is held energized over strap conductor 24I, conductor 238 and conductor I85. On segment 3| the pole changer relay is held energized over conductor 245, bridging contact I20 at the C position of switch I8, strap conductor 244, the bridging contact I20 at the D position of the switch and conductor I86. On segment 32 the pole changer relay is held energized since this segment is connected by the strap conductor 24I to conductor 238. On segment 33 the pole changer relay is held energized over conductor 246, bridging contact I29 at the D position of switch I8 and conductor I85. Segments 34 to 48, inclusive, are all strap connected by strap conductor 24I to conductor 238. The pole changer relay I 55, therefore, is maintained energized while the brush contact 92 is passing over these contacts and successively engages them. This provides a signaling period for signal apparatus, n shown, but located at the substation.

It is to be noted that when the switches I6, 11 and 18 are set in the positions indicated in Figs 1 and 6, seventeen impulses are sent over the line system through successive energization and deenergization of the pole changer relay I55, from the time the brush contact 92 engages segment 6 to its arrival on segment 22 and that each impulse is of opposite polarity to the one preceding since the pole changer relay I55 in effect reverses the battery connections to the line wires I51 and I58. The selectors at the substations each operates to move a movable contact one step toward a fixed contact on each impulse when the impulse received is of opposite polarity to the one preceding. The selectors, therefore, all step together and bring their movable contacts into engagement with the associated fixed contacts. Each selector may control signal apparatus located at the substations served by the selectors, the signal apparatus being operated when the selector moves its movable contact a predeter-,

mined number of steps and into engagement with the fixed contact. The selectors are set to hold at a certain predetermined position and will restore to normal starting position when an impulse followed by a comparatively long pause is received after they have reached the holding position. Segments 49 to I2, inclusive, are blank segments since they are not electrically connected to any of the contacts of switches I6, 11 and I8. When the brush contact 92 passes from segment 48 to segment 49, the pole changer relay is deenergized and remains deenergized for the remaining portion of the cyclic movement of the brush contact 92 over the segmental contacts of the commutator type switch I9. The selectors therefore receive a single impulse followed by a comparatively long pause and restore to normal starting position. The brush contact 92 continues to move over the segmental contacts until it reaches segment 60. Stop means are provided in the spring motor unit 9| to stop the driving of the brush contact 92 at this point. The wheel I62 at this time has completed its cyclic move-v ment and a notch 241 in the periphery of the Wheel I62 is in register with a bent end of the contact spring I69 so that at this point the contact spring IE9 is not in engagement with the wheel I62. The holding circuit for the line relay I BI is therefore open and the line relay IBI is deenergized to cause opening of the line system.

It is to be noted that when the switches I6 and 71 are in the positions indicated in Figs. 1 and 6, the bridging contacts I20 in the double elements of switches I6 and I1 bridge all contacts in the double elements except those at 0 positions and that thereare bridging contacts I20 standing between the fixed contact positions. The movable contacts I30 in the single switch elements of switch I6 normally stand at the 0 positions and not in engagement with a fixed.

contact. The movable contacts I30 in the single switch elements of switch 11 normally stand at the 0 positions and in engagement with fixed contacts. The switches I6 and II are each provided with a detent device as above mentioned. The detent device regulates movement of the movable contacts to one-step movements equal to half the distance between the fixed contact positions. A one-step movement of the switch, therefore, in switch IE will bring the movable contacts I30 into engagement with fixed contacts at positions I and will bring bridging contacts I20 of the double switch elements across all of the fixed contact positions. A second one-step movement will bring the movable contacts I 30 between fixed contact positions and will remove the bridging contacts I20 from the positions 2 in the double elements. A one-step movement in switch II will bring the movable contacts I30 off their 0 positions where they rest on fixed contacts and and midway between positions 0 and 2. The fixed contacts in the double elements of switch I? will be all bridged by the bridging contacts I20 except at position I. The blank sections of the discs H5 and H5 of the double elements will be at position I. That is to say, in this position the portion of the disc I I5 not carrying the bridging contact I20 will be in position I and all other positions will be bridged by the bridging contacts I20. It will be seen, therefore, that by turning the handles and 8I of the respective switches I6 and. I1, difierent code settings may be made and that the pole changing relay I55 may be controlled to send difierent code signals, the code signals comprising three separate series of impulses with pauses between each. series and that the total number of impulses will be seventeen. For instance, when the switches I6 and I! are each turned to position 6, the device will operate to send a code signal of three series of impulses in the order of 656 with pauses between each series. In this position of the switches there will be no bridging contacts at positions 8 in the double elements of switch IS. The movable contacts I30 of the single elements of this switch will not be in engagement with the fixed contacts. In switch 11 there will be no bridging contacts in positions 6 of the double elements. The movable contacts I30 in switch i'l, however, will be in engagement with fixed contacts at positions 6. The pole changer relay I55, therefore, will be energized when the brush con tact 92 of the commutator switch I9 engages segment (I, deenergized on segment I, energized on segment 2, deenergized on segment 3, energized on segment 4, deenergized on segment 5. This gives six impulses for the first series. The pole changer relay after being deenergized on segment 5 remains deenergized while the brush contact 92 is passing over segments 6 to H, inclusive. This provides the pause period required between the first and second series of impulses. The second series then begins, the pole changer relay being energized on segment I2, deenergized 4 on segment I3, energized on segment I4, deenergized on segment I5 and energized on segment 16. This gives five impulses for the second series. The pole changer relay after being energized on segment It remains energized while the brush contact 92 is passing over segments I! to 22, inclusive. This provides the pause period required between the second and third series of impulses. The third series then begins, the pole changer relay being deenergized on segment 23,

; energized on segment 24, deenergized on segment 25, energized on segment 26, deenergized on segment 2'! and energized on segment 28. This gives six impulses for the third series. The pole changer relay after being energized on segment 28 then remains energized while the brush contact is passing over segments 29 to 48, inclusive. This provides a ringing or other signal period for the signal device, not shown, but controlled by means of the selector at the substation selected. When the brush contact 92 passes from segment 48 to segment 49 the pole changer relay is deenergized and remains deenergized while the brush contact 92 coasts along to segment 60. A single impulse therefore is sent when the brush contact engages segment 49 and this single impulse is followed by a comparatively long pause and the selector at the selected substation restores to normal condition.

The switch I8 provides a means for increasing the number of impulses by two, four or six impulses so that a total of nineteen, twenty-one or twenty-three impulses may be sent by the impulse sending apparatus. The double elements in the switch 13 at the B, C and D positions are normally bridged by the bridging contacts I20. Under this condition a total of seventeen impulses will be sent. When the handle 82 of the switch 18 is moved to the B position the bridging contacts I are all moved one step in a clockwise direction. In this operation the bridging contact I20 at the B position is moved from the B position to the C position. The bridging contact normally at the C position is moved to the D position and the bridging contact I20 normally at the D position is moved one step away from its normal position. Therefore, the fixed contacts at the B position will be unbridged and those at the C and D positions will be bridged. Under this condition when the brush contact 92 engages segmental contact 29 the pole changer relay is deenergized. On segmental contact 30. the pole:

changer relay is energized and is then held energized While the brush contact is passing over segments 3! to 48, inclusive. This provides two additional impulses, the total number of impulses being nineteen. When the switch I8 is moved an.- other step in a clockwise direction the fixed contacts are bridged only at the D position. Under this condition the pole changer relay I55 is deenergized on. segment 3I. and energized on segment 32 and is held energized on segments 33 to 48, inclusive. This provides four additional impulses making a total of twenty-one. switch handle 82 is moved to the D. position, all of the" bridging contacts I20 in switch 18 are out of engagement with the fixed contacts. Under this condition the pole changer relay is deenergized on segment 33 and energized again on segment 34' and is held energized on. segments 35.

to 48, inclusive. This provides six additional impulses making a total of twenty-three.

The apparatus above described, therefore, provides a means for sending trains. of impulses suitable for the operation of selectors of the type above-mentioned, the selectors operating to step a movable contact one step toward a fixed. contact on each impulse of opposite polarity to the one preceding. By operating switches I6 and TI to required predetermined positions, the impulses will be divided into three series with pauses between each series, the settings of switches I6 and,

'Il determining the number of impulses in each series and where the pauses between the first and second series and between the second and third series are to occur.

in the last series. By operating only two switches, namely switches H5v and 11, the train of impulses divided into. three series is obtained. By operating switch I8 additional impulses are obtained in the last series.

The apparatus is shown and described as having a spring type motor for driving the brush contact of the commutator type switch I9. It is not necessary, however, to have a spring type motor for this purpose since other types of motors could be used in place of the spring type. There is someadvantage, however, in having the motor a spring type device since operation of the apparatus does not depend on the maintenance of a source of current supply to the motor. Another advantage is that reduction in the cost of the apparatus to a user is obtained when the user already has selector keys of the type described in Patent 1,306,054 since a selector key of this type may be used as the driving motor for the brush contact 92 of the commutator type switch I9. A comparatively large number of railway companies already have selector keys of the type above mentioned and since selector keys of this type may be used as the driving motor simply by attaching the brush contact supporting arm 90 to the key, the cost of a new motor is saved by the purchaser of the apparatus.

What is claimed is:

l. A variable impulse transmitter for transmitting variable codes of impulses each code consisting of three series of impulses with pauses therebetween, the number of impulses in each series being variable while the total number of impulses in each code signal is constant, comprising in combination, a commutator comprising spaced segmental contacts and a wiper contact successively engaging said segmental contacts, a manually operated switch comprising paired fixed When the The switch I8 provides for setting the apparatus to send additional impulses- III contacts with the contacts in each pair spaced apart, movable contacts operating in the spaces between the paired contacts to selectively bridge said paired contacts, singly arranged fixed contacts, a single wiper contact to selectively engage said singly arranged contacts, means common to said movable contacts and said single wipercontact for moving such contacts, a second manually operated switch of like structure to that above described and circuit connections between the fixed contacts, of said switches and the segmental contacts of said commutator to mak certain of said segmental contacts normally live and other of said segmental contacts normally dead, the circuit connections being such that normally there is a group of segmental contacts in which alternate contacts in the group are live and the remaining ones in the group are dead and so that the segmental contacts preceding said group are normally dead and the segmental con.- tacts following said group comprise a group of normally live contacts and a following group of permanently dead contacts and said switches being operable to selectively make the live segmental contacts dead and the dead segmental contacts live.

2. A variable impulse transmitter for transmitting variable codes of impulses each code consisting of three series of impulses with pauses therebetween, the number of impulses in each series being variable while the total number of impulses in each code signal is constant, comprising in combination, two rotary type switches the first switch designating the number of impulses in the first series and the second switch designating the number of impulses in the third series, each of said switches comprising paired series of spaced fixed contacts, movable contacts operating between said fixed contacts and selectively bridging said paired series, single series spaced fixed contacts, a wiper contact to selectively engage the fixed contacts in said single series, and means common to said movable contacts and said wiper contact for simultaneously moving the same, a commutator comprising a series of segmental fixed contacts, a wiper contact to successively engage said segmental contacts and means to drive said last-mentioned wiper contact into successive engagement with said segmental contacts, conductor wires electrically connecting the fixed contacts in said rotary switches to corresponding segmental contacts in said commutator, whereby alternate ones of said segmental contacts are normally live and the segmental contacts therebetween are normally dead, and segmental contacts preceding the alternated live and dead segmental contacts are normally dead, and said rotary switches operating to selectively change said segmental contacts from a live condition to a dead condition.

3. In a variable impulse transmitter, for transmitting variable codes of impulses, each code consisting of three series of impulses with pauses therebetween, the number of impulses in each series being variable while the total number of impulses in each code signal is constant, a commutator comprising a series of segmental fixed contacts, a wiper contact to successively engage said segmental contacts, and means to drive said wiper contact into successive engagement with said segmental contacts, two rotary type switches, each of said switches comprising three double sets of spaced fixed contacts arranged in three pairs, three sets of movable contacts, one set for each pair, arranged to selectively bridge the fixed contacts in said double sets, three single sets of spaced fixed contacts, three movable contacts, one for each of said single sets and arranged to selectively engage the fixed contacts in said single sets, means common to said three sets of movable contacts and said three movable contacts, to simultaneously move said movable contacts relative to said sets of fixed contacts and conductor Wires extending from said fixed contacts in said switches to said segmental contacts so that alternate segmental contacts in said commutator are normally live and the segmental contacts alternated therewith are normally dead, the first of said switches designating the number of impulses in the first series, the second switch designating the number of impulses in the third series, and the number of impulses in the second series being automatically determined by the segmental contacts unaffected by the setting of the two switches.

ALBERT H. MILLER. 

